\documentclass[a4paper,10pt]{book}
\usepackage{listings}
\lstset{language=Java}

\begin{document}

\tableofcontents
\include{introduction}
\include{core}
\include{summary}




\begin{thebibliography}{9}
\bibitem{fowler06}
  Martin Fowler, Kent Beck, William Opdyke, Don Roberts
  \emph{Refactoring: Improving the Design of Existing Code}.
  Addison Wesley Professional, Jun 1999
\bibitem{gamma05}
  Erich Gamma, Richard Helm, Ralph Johnson, John Vlissides
  \emph{Design Patterns: Elements of Reusable Object-Oriented Software}.
  Addison Wesley Professional, Oct 1994 
\bibitem{Hunt99}
  Andrew Hunt and David Thomas
  \emph{The Pragmatic Programmer: From Journeyman to Master}
  Addison-Wesley Professional, Oct 1999 

\end{thebibliography}


\end{document}
